The ULXD2 Handheld Transmitter with SM87A Microphone Capsule from Shure is designed for compatibility with Shure's ULX-D wireless systems. It has an interchangeable SM87A capsule and is set to Shure's X52 frequency band that operates between 902 to 928 MHz.The ULXD2 has AES 256-bit encryption that keeps your signal secure. Featuring Shure's proprietary Gain Ranging, the ULXD2's dynamic range is optimized based on the input source and eliminates the need for transmitter gain adjustments. It has a lightweight, 12-ounce metal body with a backlit LCD menu with frequency and power lockout to avoid accidental setting changes. Powered by two AA batteries or the optional SB900 rechargeable battery pack, the ULXD2 has external charging contacts and is compatible with SBC200 dual docking charger.